Add a symbol __curPos that expands to the current source location

I.e. an attribute set { file = <string>; line = <int>; column = <int>; }.
This commit is contained in:
Eelco Dolstra 2013-11-18 20:14:54 +01:00
parent 90b5e69284
commit fc33fd86b7
7 changed files with 43 additions and 2 deletions

View file

@ -142,6 +142,9 @@ EvalState::EvalState()
, sOutputs(symbols.create("outputs"))
, sOutputName(symbols.create("outputName"))
, sIgnoreNulls(symbols.create("__ignoreNulls"))
, sFile(symbols.create("file"))
, sLine(symbols.create("line"))
, sColumn(symbols.create("column"))
, repair(false)
, baseEnv(allocEnv(128))
, staticBaseEnv(false, 0)
@ -1039,6 +1042,16 @@ void ExprConcatStrings::eval(EvalState & state, Env & env, Value & v)
}
void ExprPos::eval(EvalState & state, Env & env, Value & v)
{
state.mkAttrs(v, 3);
mkString(*state.allocAttr(v, state.sFile), pos.file);
mkInt(*state.allocAttr(v, state.sLine), pos.line);
mkInt(*state.allocAttr(v, state.sColumn), pos.column);
v.attrs->sort();
}
void EvalState::strictForceValue(Value & v)
{
forceValue(v);

View file

@ -94,7 +94,8 @@ public:
SymbolTable symbols;
const Symbol sWith, sOutPath, sDrvPath, sType, sMeta, sName, sValue,
sSystem, sOverrides, sOutputs, sOutputName, sIgnoreNulls;
sSystem, sOverrides, sOutputs, sOutputName, sIgnoreNulls,
sFile, sLine, sColumn;
Symbol sDerivationNix;
/* If set, force copying files to the Nix store even if they

View file

@ -130,6 +130,11 @@ void ExprConcatStrings::show(std::ostream & str)
}
}
void ExprPos::show(std::ostream & str)
{
str << "__curPos";
}
std::ostream & operator << (std::ostream & str, const Pos & pos)
{
@ -315,6 +320,10 @@ void ExprConcatStrings::bindVars(const StaticEnv & env)
(*i)->bindVars(env);
}
void ExprPos::bindVars(const StaticEnv & env)
{
}
/* Storing function names. */

View file

@ -282,6 +282,13 @@ struct ExprConcatStrings : Expr
COMMON_METHODS
};
struct ExprPos : Expr
{
Pos pos;
ExprPos(const Pos & pos) : pos(pos) { };
COMMON_METHODS
};
/* Static environments are used to map variable names onto (level,
displacement) pairs used to obtain the value of the variable at

View file

@ -355,7 +355,12 @@ expr_select
;
expr_simple
: ID { $$ = new ExprVar(CUR_POS, data->symbols.create($1)); }
: ID {
if (strcmp($1, "__curPos") == 0)
$$ = new ExprPos(CUR_POS);
else
$$ = new ExprVar(CUR_POS, data->symbols.create($1));
}
| INT { $$ = new ExprInt($1); }
| '"' string_parts '"' {
/* For efficiency, and to simplify parse trees a bit. */

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@ -0,0 +1 @@
[ 3 7 4 9 ]

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@ -0,0 +1,5 @@
# Bla
let
x = __curPos;
y = __curPos;
in [ x.line x.column y.line y.column ]